#include<stdio.h>
#include<stdlib.h>
#define max 50000
int *a[max];
int pord[max],n,nr,viz[max];
unsigned int m;
void citire()
{scanf("%d%d",&n,&m);
for(int i=1;i<=n;i++)
{a[i]=(int *)realloc(a[i],sizeof(int));
a[i][0]=0;
}
int x,y;
for(unsigned int i=1;i<=m;i++)
{scanf("%d%d",&x,&y);
a[x][0]++;
a[y][0]++;
a[x]=(int *)realloc(a[x],(a[x][0]+1)*sizeof(int));
a[x][a[x][0]]=y;
a[y]=(int *)realloc(a[y],(a[y][0]+1)*sizeof(int));
a[y][a[y][0]]=x;
}
}
void dfs(int x)
{viz[x]=1;
for(int i=1;i<=a[x][0];i++)
	if(!viz[a[x][i]])
		dfs(a[x][i]);
	pord[++nr]=x;
}
int main()
{freopen("top.in","r",stdin);
freopen("top.out","w",stdout);
citire();
dfs(1);
for(int i=n;i>1;i--)
	printf("%d ",pord[i]);
printf("%d",pord[1]);
return 0;
}